The present invention relates to a synergistic fungicidal and/or bactericidal composition comprising dodine and a compound of the anilino-pyrimidine family, and to a method of using this composition for the curative or preventative protection of crops against fungal attack.
It is always desirable to improve the range of activity and efficacy of such fungicidally active compounds, or to make them more potent by combining them with other molecules in order to obtain an improved product or else to prevent the appearance of fungal strains which are resistant.
Equally, it is very desirable to have available fungicidal products which have an improved duration of action so that the number of plant protection treatments required for good control of the parasites can be spaced out over the course of time.
In any case, it is particularly advantageous to be able to reduce the quantity of chemical products sprayed in the environment while guaranteeing effective protection of the crops against fungal attack.
It has now been found that one (or more) of the above aims can be achieved by the fungicidal and/or bactericidal composition according to the present invention.
The present invention primarily therefore relates to a synergistic fungicidal and/or bactericidal composition comprising, as compound A, dodine, which is also known as dodecylguanidine monoacetate, and at least one fungicidal compound B selected from the group comprising a compound of the anilino-pyrimidine family, that is to say B is chosen from the group comprising cyprodinil, pyrimethanil or mepanipyrim.
The fungicidal and/or bactericidal composition according to the invention advantageously comprises the components A and B in a weight ratio A/B of between 1/26 and 160/1, preferably between 1/4 and 60/1, especially advantageously in a ratio of between 3/8 and 9/1.
Naturally, this fungicidal and/or bactericidal composition can contain a single compound B or more than one such compound, for example, 1, 2 or 3 compounds B, depending on the intended use.
Amongst the more particularly preferred meanings of the above-defined compound B, pyrimethanil is especially preferred. Quite unexpectedly, the composition according to the invention improves in a remarkable manner the activity of active materials taken separately for a number of fungi which are particularly harmful to crops, such as, in particular, grapevine or the potato family. This improvement manifests itself especially by a reduced dosage of each of the constituents, which is particularly advantageous for the user and the environment. The fungicidal and/or bactericidal product (mixture) thus exhibits synergistic properties which are borne out by applying the method defined by Limpel L. E., P. H. Schuldt and D. Lammont, 1962, Proc. NEWCC 16:48-53, using the following formula, also called Colby formula:
E=X+Yxe2x88x92X.Y/100
in which:
E is the expected percentage of inhibition of the growth of the fungus by a mixture of the two fungicides A and B at defined doses, respectively equal to a and b;
X is the observed percentage of inhibition by the fungicide and/or bactericide A at the dose a,
Y is the observed percentage of inhibition by the fungicide and/or bactericide B at the dose b. When the observed percentage of inhibition for the mixture is greater than E, there is synergism.
When component B is pyrimethanil, the ratio A/B is preferably between 1/4 and 60/1, this ratio especially advantageously being between 3/8 and 9/1, this ratio most preferably being 3/1 for all of the crops under consideration.
The structures which correspond to the common names of the active materials A and B are given in at least one of the 2 following works:
xe2x80x9cThe pesticide manualxe2x80x9d, edited by Clive TOMLIN, and published by the British Crop Protection Council, 11th Edition, 1997 (pages 451, 1068, 319 and 784);
The xe2x80x9cIndex phytosanitaire 1998xe2x80x9d, edited by the Association de Coordination Technique Agricole, 34th Edition.
The fungicidal and/or bactericidal composition according to the invention comprises, as active material, a compound A and at least one compound B as a mixture with solid or liquid agriculturally acceptable carriers and/or surfactants which are also agriculturally acceptable. Substances which can be used in particular are the usual inert carriers and the usual surfactants. These compositions extend not only to compositions which are ready to be applied to the crop to be treated by means of a suitable device, such as a sprayer, but also to concentrated commercial compositions which must be diluted before being applied to the crop. By active material there is to be understood the combination of at least one compound A with at least one compound B.
These compositions can also contain any type of other ingredients such as, for example, protective colloids, adhesives, thickeners, thixotropes, penetrants, stabilizers, sequestering agents and the like. More generally, the compounds A and B can be combined with all solid or liquid additives which are conventionally used in the art of formulation.
Generally speaking, the compositions according to the invention usually contain from 0.05 to 95% (by weight) of active material, one or more liquid or solid carriers and, if appropriate, one or more surfactants.
The term xe2x80x9ccarrierxe2x80x9d is to be understood as meaning in the present text a natural or synthetic organic or mineral material with which the active material is combined to facilitate its application to the aerial parts of the plant. This carrier is thus generally inert and must be agriculturally acceptable, especially by the treated plant. The carrier may be solid (clays, natural or synthetic silicates, silica, resins, waxes, solid fertilizers and the like) or liquid (water, alcohols, especially butanol, and the like).
The surfactant may be an ionic or nonionic emulsifier, dispersant or wetter, or a mixture of such surfactants. By way of example there may be mentioned salts of polyacrylic acids, of lignosulphonic acids, of phenolsulphonic acids or of naphthalenesulphonic acids, polycondensates of ethylene oxide and fatty alcohols or fatty acids or fatty amines, substituted phenols (especially alkylphenols or arylphenols), salts of sulphosuccinic esters, taurine derivatives (especially alkyl taurates), phosphoric esters of alcohols or of polyoxyethylated phenols, esters of fatty acids and polyols, and derivatives of the above compounds which have a sulphate, sulphonate and phosphate function. The presence of at least one surfactant is generally indispensable when the active material and/or the inert carrier are not soluble in water and when the application vehicle is water.
The compositions according to the invention for use in agriculture can therefore contain the active material within very wide limits of from 0.05% to 95% (by weight). Their surfactant content is advantageously between 5% and 40% by weight. Unless otherwise specified, the percentages given in the present description including the claims are by weight.
These compositions according to the invention, themselves, come in a wide variety of solid or liquid forms.
As solid forms of compositions there may be mentioned powders for dusting (whose active material content may be as high as 100%) and granules, especially those obtained by extrusion, by compacting, by impregnating a granulated carrier, by granulation of a powder (the active material content in these granules being between 0.5 and 80% in the last-mentioned cases), tablets or effervescent tablets.
The fungicidal and/or bactericidal composition according to the invention may also be used in the form of powders for dusting; a composition comprising 50 g of active material and 950 g of talc may also be used; a composition comprising 20 g of active material, 10 g of finely divided silica and 970 g of talc may also be used; these constituents are mixed and ground, and the mixture is applied by dusting.
As liquid forms of compositions, or forms intended to give liquid compositions upon application, there may be mentioned solutions, in particular water-soluble concentrates, emulsions, concentrated suspensions, aerosols, wettable powders (or sprayable powders), pastes, and gels.
Concentrated suspensions which can be applied by spraying are prepared in such a way that a stable fluid product is obtained which does not settle, and they usually contain 10 to 75% of active material, 0.5 to 15% of surfactants, 0.1 to 10% of thixotropes, 0 to 10% of suitable additives such as antifoams, corrosion inhibitors, stabilizers, penetrants and adhesives, and, as carrier, water or an organic liquid in which the active material is sparingly, or not, soluble: certain organic solid materials or mineral salts may be dissolved in the carrier to help prevent settling, or as antifreeze agents for the water.
By way of example there is now given a composition of a concentrated suspension:
Wettable powders (or sprayable powders) are usually prepared in such a way that they contain 20 to 95% of active material; they usually contain, in addition to the solid carrier, 0 to 30% of a wetter, 3 to 20% of a dispersant, and, if necessary, 0.1 to 10% of one or more stabilizers and/or other additives, such as penetrants, adhesives, anticaking agents, colorants and the like.
To obtain sprayable powders, or wettable powders, the active materials are mixed intimately with the additives in suitable mixers and the mixtures are ground in mills or other suitable grinders. This gives sprayable powders with advantageous wetting and suspending properties; they can be suspended in water to give any desired concentration, and these suspensions are very advantageously suitable for foliar application to the plants, in particular.
Instead of wettable powders, pastes may be made. The conditions and modes of making and using these pastes are similar to those for wettable powders or sprayable powders.